6L80- Drive it till it quits, rebuild local or replace with rebuilt GM part?

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Ibustbravo

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This is like a Zen and the art of motorcycle maint question.

I have a 15 Yukon Denali with the 6.2L, just replaced the engine with a core I rebuilt from ebay. Now that the engine is running great, it's glaringly obvious the trans is on it's last leg. Brought it to a trans shop I trust and it's as bad as I thought.

Do I drive it till the trans quits and replace with rebuilt GM part after it totally quits? Or rebuild local before it's destroyed? It's going to cost near $6K($5800 US) to rebuild the trans here locally, there's no getting around it, these are expensive transmissions. Local shops offer a 2yr warranty.

I can buy a GM factory refurbished unit with a 3yr warranty for 4300 and change.. Here's the issue though and I hope I'm not alone here- I have serious trust issues with GM dealerships and warranty's. I feel like I got the the USMC green weenie with no lube when I bought this truck. I mean, it's a familiar feeling but it's been a few years since we've had relations like that.. heheh..

What would you do? Spend up to 6K with people you trust with less warranty or spend 4500 with a part from the factory?
 

NickTransmissions

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This is like a Zen and the art of motorcycle maint question.

I have a 15 Yukon Denali with the 6.2L, just replaced the engine with a core I rebuilt from ebay. Now that the engine is running great, it's glaringly obvious the trans is on it's last leg. Brought it to a trans shop I trust and it's as bad as I thought.

Do I drive it till the trans quits and replace with rebuilt GM part after it totally quits? Or rebuild local before it's destroyed? It's going to cost near $6K($5800 US) to rebuild the trans here locally, there's no getting around it, these are expensive transmissions. Local shops offer a 2yr warranty.

I can buy a GM factory refurbished unit with a 3yr warranty for 4300 and change.. Here's the issue though and I hope I'm not alone here- I have serious trust issues with GM dealerships and warranty's. I feel like I got the the USMC green weenie with no lube when I bought this truck. I mean, it's a familiar feeling but it's been a few years since we've had relations like that.. heheh..

What would you do? Spend up to 6K with people you trust with less warranty or spend 4500 with a part from the factory?
I'd have it built to your requirements by people you trust. The trick is finding such people.

If you have found a shop that you have built rapport with and they seem to be knowledgeable and competent, I'd have them build it.

Check out my 6L80 Info thread for mode details around performance upgrades but here's a few upgrades that I do to all of those transmissions:
> Sonnax billet 1-2-3-4 apply piston
> Sonnax Zip Kit
> Sonnax 3-5-Reverse apply ring (gives you one addl steel and friction in that clutch pack)
> Sonnax 4-5-6 piston kit - 36 tooth friction design (gives you one addl steel and friction in that clutch pack using factory spec 36-tooth frictions)
> There's a 4-5-6 piston kit available that uses Powerglide spec clutches that have 45 teeth but you also have to purchase the matching 45-tooth billet clutch hub

If you're making some more serious power, do these:
> Sonnax billet 4-5-6 clutch hub (The factory piece likes to snap in half if power levels start to get up there)
> Rear planetary carrier w/billet drive plate

Also, make sure you have them run a delete kit or pill flip on the thermal bypass valve - that stupid thing is always a threat to fail, get stuck and overheat the trans...Transmission temps should never run more than about 200 degrees max (I prefer 180 degrees typical max running temps but newer Dex6 should be able to handle 200 before you'd get concerned).
 
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Ibustbravo

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I'd have it built to your requirements by people you trust. The trick is finding such people.

If you have found a shop that you have built rapport with and they seem to be knowledgeable and competent, I'd have them build it.

Check out my 6L80 Info thread for mode details around performance upgrades but here's a few upgrades that I do to all of those transmissions:
> Sonnax billet 1-2-3-4 apply piston
> Sonnax Zip Kit
> Sonnax 3-5-Reverse apply ring (gives you one addl steel and friction in that clutch pack)
> Sonnax 4-5-6 piston kit - 36 tooth friction design (gives you one addl steel and friction in that clutch pack using factory spec 36-tooth frictions)
> There's a 4-5-6 piston kit available that uses Powerglide spec clutches that have 45 teeth but you also have to purchase the matching 45-tooth billet clutch hub

If you're making some more serious power, do these:
> Sonnax billet 4-5-6 clutch hub (The factory piece likes to snap in half if power levels start to get up there)
> Rear planetary carrier w/billet drive plate

Also, make sure you have them run a delete kit or pill flip on the thermal bypass valve - that stupid thing is always a threat to fail, get stuck and overheat the trans...Transmission temps should never run more than about 200 degrees max (I prefer 180 degrees typical max running temps but newer Dex6 should be able to handle 200 before you'd get concerned).
Yea, I saw your post and have this page pulled up already. Thanks for the input!

C
 

adventurenali92

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This is like a Zen and the art of motorcycle maint question.

I have a 15 Yukon Denali with the 6.2L, just replaced the engine with a core I rebuilt from ebay. Now that the engine is running great, it's glaringly obvious the trans is on it's last leg. Brought it to a trans shop I trust and it's as bad as I thought.

Do I drive it till the trans quits and replace with rebuilt GM part after it totally quits? Or rebuild local before it's destroyed? It's going to cost near $6K($5800 US) to rebuild the trans here locally, there's no getting around it, these are expensive transmissions. Local shops offer a 2yr warranty.

I can buy a GM factory refurbished unit with a 3yr warranty for 4300 and change.. Here's the issue though and I hope I'm not alone here- I have serious trust issues with GM dealerships and warranty's. I feel like I got the the USMC green weenie with no lube when I bought this truck. I mean, it's a familiar feeling but it's been a few years since we've had relations like that.. heheh..

What would you do? Spend up to 6K with people you trust with less warranty or spend 4500 with a part from the factory?
You know the saying… you get what you pay for….. why even chance it with a dealership whose techs and skills are a complete unknown…. Yeah it sucks to have to shell out more for the local shop. But their expertise in rebuilding transmissions is worth every penny. And more than likely you’ll shell out the 6 grand and not have to look back…. Sticker shock sucks but it’ll suck more of the dealer doesn’t do it right and it ends up costing you more in the long run with more trips to the dealer to get it handled correctly rather than one and done at the trusted local transmission shop.
 

L8T BURB

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I am by no means a transmission expert, so I'll lead with that.

When looking at it from strictly a financial aspect...my thoughts here are that despite the possible lower quality build that you'd get from a GM transmission...the fact that you would have a nationwide warranty that can be utilized at all GM dealerships that includes 100% parts AND labor, and it's even a little cheaper on the front end purchase...I would definitely go with the GM unit here. Additionally, a lot of GM dealerships offer complimentary loaners, which would be another added perk of going this route.

Lets think in terms of "what ifs".... What if the transmission you purchase (regardless of independent shop trans or dealership), fails once per year over the next 3 years. Which route would cost you more from that standpoint?

The GM route just (to me) seems like it would be the least "financially volatile" route in my opinion as everything I have been told by my local GM service manager is that the warranty that accompanies those transmissions is 100% no frills, no cost warranty with no deductibles.

Hope this helps!
 
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Ibustbravo

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I am by no means a transmission expert, so I'll lead with that.

When looking at it from strictly a financial aspect...my thoughts here are that despite the possible lower quality build that you'd get from a GM transmission...the fact that you would have a nationwide warranty that can be utilized at all GM dealerships that includes 100% parts AND labor, and it's even a little cheaper on the front end purchase...I would definitely go with the GM unit here. Additionally, a lot of GM dealerships offer complimentary loaners, which would be another added perk of going this route.

Lets think in terms of "what ifs".... What if the transmission you purchase (regardless of independent shop trans or dealership), fails once per year over the next 3 years. Which route would cost you more from that standpoint?

The GM route just (to me) seems like it would be the least "financially volatile" route in my opinion as everything I have been told by my local GM service manager is that the warranty that accompanies those transmissions is 100% no frills, no cost warranty with no deductibles.

Hope this helps!
Ok, thanks for your input. Hahah.. To be candid, if this damned truck broke down once a year for the next few years I'd toss a flair in it and let it burn like I should have when the engine blew up. This thing is costing us a fortune in repairs.

I digress.. To the USAA insurance adjusters here.. I'm kidding!

I found this article in Alldata.com and it's really swaying my decision here.,

Identifying Non-GM (Aftermarket) Engine Calibrations for Gasoline Engines Using Tech 2® or GDS 2 (U.S. and Canada)​


These ECU and TCU's have versioning history of the last 10 changes.. and I do my own tuning.. I'd be breaking warranty because the techs will check. Not sure how that works with a reman unit but.. it's almost not worth the risk knowing that these warranty's have narrow rules to begin with.

C
 

B-train

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I see both sides and still lean towards a GM trans with a nationwide warranty as @interceptor859 stated. I guess it depends on the type of tuning you do for what it may need to hold up to. If its aggressive, then maybe a built trans like @NickTransmissions said. If it's mild, I may just not worry about it and take my chances with GM for the better price and warranty.
 

justchecking

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To the OP, for my own understanding (because I may be faced with the same dilemma): $5800 was complete removal, rebuild, install with 2 year warranty from a local shop. $4300 was GM rebuilt trans with 3 year warranty NOT INCLUDING removal and install labor. Correct?
 
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Ibustbravo

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To the OP, for my own understanding (because I may be faced with the same dilemma): $5800 was complete removal, rebuild, install with 2 year warranty from a local shop. $4300 was GM rebuilt trans with 3 year warranty NOT INCLUDING removal and install labor. Correct?
Yes you have it right.

I'm guessing ~$800 to remove and install based on the shop hours from alldata and 100/hr shop rate. It looks like a push to me.
 

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